No Apocalypse This Friday

Stop worrying about the Mayan prophecy of doom that supposedly is due this week.  They didn't predict any such thing. 
The Mayan calendar runs out this Friday, on the 21st.  My calendar on my office wall runs out the 31st.  Both are intended to roll over and begin again.

It is mildly interesting, in a trivial kind of way, that the Mayan calendar does roll over, like an odometer, to all zeroes on Friday.  But the assumption that this foretells cataclysm, disaster, and the end of the world is something that other people (not the Mayans) started importing into the conversation in the mid-1970's.  The Mayans actually expected events to take to place on future calendars beyond this one, many thousands of years into the future. 

Furthermore, when we say that the Mayans predicted the end of the world, we assume that they believed in such a thing.  Many cultures have no concept of an apocalypse, judgment day, or end of the world.  Many non-Western cultures (specifically without influence from Judeo-Christian sources) believe in a cyclical world of reincarnation or rebirth that continues, in one form or another, forever.

Either way, there is nothing to fear from the Mayans this week.

Also:

• Here's some background info from NASA.
• More from NASA here.
• And a number of resources here.